A. Field of the Invention
The present invention pertains generally hybrid networks and more specifically voice communications over hybrid networks.
B. Description of the Background
Various forms of communication through the PSTN network have greatly increased the demand for PSTN numbers and dedicated PSTN lines. For example, the proliferation of cell phones has greatly increased the demand for PSTN numbers. Dial-up access to the Internet, as well as the ubiquitous use of fax machines has resulted in a demand for dedicated PSTN lines for those services in addition to normal voice PSTN lines. For example, a single individual may have an office line, a home business line, a dedicated line at home for fax and dial-up modem access to Internet service providers (ISP) and a separate home telephone line. In addition, that individual may also have a car phone and a cell phone. Calling parties may be unwilling to call these plurality numbers in an attempt to contact an individual.
Also, the use of PSTN services can be expensive. For example, long distance charges, monthly charges for multiple dedicated lines and similar charges can be as much as several hundred dollars a month for an individual, and even more for businesses.
To overcome these problems, various products have been developed such as the xe2x80x9cCONTACTxe2x80x9d product provided by MCI Worldcom that is a one number location service. The CONTACT product uses a single number that is assigned to each subscriber. A calling party dials the number that is assigned to a called subscriber to access a calling profile for that subscriber. An automatic call processing system then calls each of the numbers in the stored calling profile sequence of numbers for that subscriber in an effort to contact the subscriber. In this manner, a single number can be used to access the subscriber, thereby eliminating many of the frustrations associated with attempting to contact an individual that has a plurality of PSTN numbers. Although the one number access products are effective in locating a user at various PSTN lines, to date, such services have not been able to connect a user to a data device on a data network, such as the Internet to provide IP telephony calls.
As an alternative to PSTN calls, IP telephony has become a popular and inexpensive manner of providing voice communications between users that are connected to the Internet. Some of the advantages of IP telephony are that it allows for widespread voice communication in an inexpensive manner. Increasing bandwidth on the Internet as a result of newer, high speed servers and a better infrastructure of fiber optic cable connections has allowed IP telephony connections to produce high clarity calls that in many cases are indistinguishable from normal PSTN connections. IP Telephony may also have the beneficial advantage of decreasing the current demand for PSTN numbers for the various types of PSTN communications that currently exist.
Further, in an effort to provide an alternative to having a dedicated line for dial-up services to ISPs, local exchange carriers (LECs) have offered a service called Internet Call Waiting. Internet Call Waiting products operate by detecting when a particular PSTN line is busy. The LEC then forwards the call to the subscriber""s ISP. The subscriber""s ISP recognizes the dialed number of the subscriber using dialed number identification service (DNIS), determines that the subscriber is logged on and generates a message that is sent to the called party that a PSTN call is being received. The subscriber may then quickly log off and answer the PSTN call. The Internet Call Waiting products provide a convenient way to share the resources of a single line and eliminate the proliferation of multiple PSTN lines.
There are many limitations, however, of the Internet Call Waiting systems. For example, many LECs do not provide such service. Such service requires LEC forwarding which many LECs have not yet provided to customers. Further, most Internet Call Waiting services require the user to be subscribed to services from a specific ISP. The user may not wish to subscribe to services from that particular ISP. Further, Internet Call Waiting only works on the line to which that service is subscribed. In other words, the Internet Call Waiting services do not allow the user to log on using a different PST line.
Considering the advantages of these disparate products, it would be advantageous to have a one number location service that is capable of contacting an individual at one of several destinations that includes an IP logical address and that will connect a call to the IP physical address at which the called party is located. In other words, it would be advantageous to provide a service that would allow completion of calls from a PSTN line to a data device connected to a data network and that would allow the data device to be connected to the data network at any desired location utilizing a one number location service.
The present invention overcomes the disadvantages and limitations of the prior art by providing such a service. The present invention utilizes a single number location service that is also capable of connecting a PSTN call to a data device at a network destination that is at least one of the destinations in the called party""s profile. Unlike Internet Call Waiting services, a user can be connected to the data network at any desired location. The present invention uses a logical address that is stored in a directory together with the physical address of the location where the user is connected to the system. A caller can then call a single PSTN number assigned to a user which is routed to an automatic call processing system. The automatic call processing system accesses a calling profile for the called number and sequentially calls each of the numbers in the call profile. The call profile may include one or more logical addresses (IP alias). The automatic call processing system recognizes the IP alias as a destination on the data network and queries the directory to determine if the data device is logged on to the IP network and to obtain the physical IP address of the data device on the network. If the data device has registered an IP address, that indicates that the device is logged on to the system and that the PSTN call can be routed to a translator for subsequent routing to the data device on the data network.
The present invention may therefore comprise a method of communicating a voice call from a caller on a PSTN network to a called party on a data device that is connected to a data network at an address on the data network that may change each time the data device is connected to said data network comprising the steps of registering the address of the data device with a directory, routing a call from the caller on the PSTN network to a sequence of destinations that are assigned to the called party such that at least one of the destinations in the sequence is a destination on the data network, determining the address of the data device on the data network, routing the call from the PSTN network through a translator to the address on the data network whenever the data device has registered the address with the directory and the call is routed to the destination on the data network.
The present invention may further comprise of a system for placing a call from a calling party to a called party over a hybrid PSTN/data network comprising, a telephone connected to the PSTN network that originates a call from the calling party over the PSTN network, a data device that is connected to the data network, a directory connected to the data network that registers an address on the data network for the data device whenever the data device is connected to the data network, an automatic call processing system that receives the call and sequentially routes the call in accordance with a calling profile having a plurality of destinations of which at least one destination is a destination on the data network, a translation device connected to both the PSTN network and the data network that queries the directory to determine if the data device has registered an address on the data network and to route the call over the data network to the address whenever the data device has a registered address on the data network.
The advantages of the present invention are that a seamless connection can be made to complete an IP telephony call to a data device on a data network from a PSTN number using a single number locator service. The present invention has all the advantages of the single number location services, but in addition, also allows for IP telephony calls to be completed to data devices in a seamless manner. In this fashion, the PSTN network can act as a front end connection to the vast Internet data network. The use of a single number assigned to an individual will allow the front end PSTN network to interface and locate an individual at any physical IP address at which the user is connected. Heretofore, a simple and convenient system for interfacing the PSTN network using a single PSTN number for connection to an individual on an IP network has not been available.
Individual LEC lines are not required for each data device utilizing the principles of the present invention. Data devices no longer are required to have a static location (IP address) via a dedicated PSTN line. Management of dedicated LEC lines for each data device is cumbersome and is very costly. The single number location service coupled with a directory for locating a user that may have numerous data devices on which a single logical address is used greatly reduces the cost and inconvenience of using a dedicated LEC line for each data device.
The present invention also provides other advantages. Data devices such as personal data assistants (PDAs) may constantly be connecting and reconnecting to an IP network at different locations since the PDAs are portable devices that may be connected to ISPs or local networks through wireless connections such as RF, IR, etc. Each connection and reconnection of the PDA will result in a different physical IP address associated with the logical address for that PDA. The directory (gatekeeper) of the present invention stores the IP address with the logical address of the data device to provide the physical location and log on status of the data device.
Also, since calls that are directed to a logical IP address (IP alias) in a called party""s calling profile are routed directly to a translator (IP/telephony gateway), switching functions are not provided by the LEC at the called party""s end. Hence, connection charges by the local LEC of the called party are eliminated.
Further, the only PSTN charges associated with the call are the LEC charges at the calling party end which result from connection of the calling party to the automatic call processing system. Hence, long distance calls to any dynamic location at which the user is connected to the data network can be made inexpensively as an IP telephony call.
Additionally, the varying grades of service and other limitations of a local LEC at the called party""s location are avoided.
Further, the proliferation of PSTN numbers is reduced since a single number access service is provided together with connection of a call to a data device. Also, IP telephony clients that are currently available allow a user to conduct both the IP telephony call and remain logged on to the Internet simultaneously since the data packets for the voice data are routed to the IP telephony client while the data packets for the data device are routed to the IP browser. Unlike Internet Call Waiting, the data device user can then operate the data device and simultaneously conduct an IP telephony call.